The Digester

Kristi Noem ousted as DHS secretary amid contract and ethics scrutiny

Homeland Security Secretary Kristi Noem was removed after two days of bruising congressional hearings that exposed questions about no-bid ad contracts, planned migrant detention warehouses, a leased private plane, and her adviser Corey Lewandowski’s role in contract approvals. Lawmakers have opened document requests and signaled possible investigations into procurement and potential false statements to Congress.

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Correction tensor generalises Cunningham drag law for arbitrary particle shapes across Knudsen numbers

A new, parameter free form of the Cunningham correction factor is proposed and extended into an element wise correction tensor that predicts gas drag on slow-moving, non-spherical particles across the full Knudsen number range; the heuristic matches sphere experiments, DSMC and kinetic solutions for spheroids and a thin disc with generally small errors but still needs further testing and extension to rotational coupling.

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